Andén Cero (Platform Zero) is an interpretation centre for Madrid’s Metro, opened in 2006, of which the main part is in the Chamberi station which was closed in 1966 because it was impossible to extend its platforms when train lengths were increased. Chamberi station was one of eight on the first line of the Metro and opened in 1919. Visitors access the centre by a modern spiral staircase and a glass elevator. They see a 20-minute film on the history of the Metro system in the entrance hall from which passengers once came into the station from the street. The film and displays show how the Metro transformed Madrid from the early years of the twentieth century, its civil and mechanical engineering, the ways in which it was marketed and its uses for advertising. The ticket office has been restored to the condition in which it operated in the 1920s. The station, designed by Antonio Palacios (1874-1945) is remarkable for the use of ceramic tiles lining the arch above the platforms and in advertisements. Metro trains continue to pass through the station between glass barriers along the platform edges.
Andén Cero also includes the Nave de Motores de Pacifico, the power station for the Metro in which there are three large diesel engines, driving generators, together with the associated alternators. The power station could also contribute power to the city network. It was run down from the 1950s and finally closed in 1976. Like the Chamberi station it was designed by Antonio Palacios.